[Mr. Breeze]

Hey all. I have been getting gradually worse mileage lately (~15.5 as opposed to 17+ this summer). Also, since I installed the OME lift my mileage has dropped another 1.5+mpg since Friday. I originally thought it might be a lead foot problem :grin:, so I've been careful but it's gotten no better. I know these trucks are notoriously thirsty, however I didn't expect the mileage change to be so drastic. Is there something wrong here or is 14mpg normal under these circumstances?

 

[drewbie]

Winter fuel mix kills mileage too.

 

[The other Sean]

I get high 14's all winter. High 15's and the occasional 16's all summer.

 

[PyroMedic]

I have a 5" lift and 33's and am getting 16MPG driving a mix of highway and street. The winter kills MPG and the cold air doesn't help with the heating of the engine at all either haha

 

[Archer22]

I wouldn't put too much credence in the winter/summer blend fuel thing unless you live in a far northern climate. I used to work for a national fuel station outfit and other than the far northern states, we did not sell winter/summer blends except for bio-diesel to prevent gelling. We sold one mix of gasoline, period. (aside from ethanol blends)

If you fuel at one specific gas station repeatedly for every tank and you know they run different blends depending on the time of year, then sure it may have to do with the mix. Otherwise, I wouldn't put too much hope in it being just the fuel blend causing mileage probs.

 

[Mr. Breeze]

I wouldn't put too much credence in the winter/summer blend fuel thing unless you live in a far northern climate. I used to work for a national fuel station outfit and other than the far northern states, we did not sell winter/summer blends except for bio-diesel to prevent gelling. We sold one mix of gasoline, period. (aside from ethanol blends)

If you fuel at one specific gas station repeatedly for every tank and you know they run different blends depending on the time of year, then sure it may have to do with the mix. Otherwise, I wouldn't put too much hope in it being just the fuel blend causing mileage probs.

My thoughts also. Especially since it's been A: running 15.5-16mpg all winter so far and it has been warmer lately, and B: only changed in the last week. Down to 13.5mpg now, so I'm almost positive something else is going on.

I have a 5" lift and 33's and am getting 16MPG driving a mix of highway and street. The winter kills MPG and the cold air doesn't help with the heating of the engine at all either haha

You've just pretty much verified I have an issue. I still have 32s on and not lifted nearly as high.

 

[Colo.Frontier]

Since doing the 2" lift on my '15 Frontier, I've only lost maybe .5 mpg, but I also have Hefty steel skids for the extra 400 lbs of weight. Also, Colorado's winter blend fuel, which I see you're in the Springs, can cause reduced fuel mileage. Try running a can of BG44K with your next full tank and give it a tank or two after that.

 

[PyroMedic]

My thoughts also. Especially since it's been A: running 15.5-16mpg all winter so far and it has been warmer lately, and B: only changed in the last week. Down to 13.5mpg now, so I'm almost positive something else is going on.



You've just pretty much verified I have an issue. I still have 32s on and not lifted nearly as high.

I do have a manual and coast alot down the hills here in Colorado that do help out a little haha

Sent from my SM-G930T using Tapatalk

 

[shift_RUSH]

While skids plates are added weight, they also assist in aero-airflow under the truck.

 

[Mr. Breeze]

Down to about 12.2mpg. Does anyone have any ideas as to why I dropped so much so fast?

 

[MrBojangles]

Driveshaft angles possibly. Your lift changed the relationship between the end of the transmission and the front of the rear axle. Even with shims correcting rear axle angle by 2-3 degrees, you aren't correcting the "kink" in the driveshaft cv joint immediately behind the trans. Very small changes in driveshaft angle will make considerable changes in drive efficiency and the ability for the vehicle to coast.

Did you use shims on the rear axle during lift?
http://www.nissteclifts.com/components/com_virtuemart/shop_image/product/3_Degree_Rear_Ax_4e0fe0eef3924.jpg

Sadly there is nothing that can be done to correct for the angles on the front end cvs, but any degree change to an axle/driveshaft with cv joints will rob the system of previous efficiency.

Have you experienced any vibrations? Sometimes after a lift a minor imbalance of a drive line gets worse and the rotating mass out of balance can strain the system.

Just spitballing at this point, but the driveshaft angle change isn't enough to justify the entire change you are experiencing. Possibly with the addition of bad fuel. I have an OME rear leaf pack w/ shims and still saw an overall loss with a 2.5" lift/level of about 2.5-3 mpg

 

[4thNissan'05]

Looks like you have an '06... Check the plugs and air filter. I changed out these on my '05 when I bought it and got an MPG easy. It could also be that your alignment is off and you're pushing the truck (toe-in/out) everywhere instead of rolling? Other than that, you could do a fuel system cleaning... sometimes it's just time!

 

[ib17p4x]

Alignment done after your lift? Could be out of spec if not and causing more resistance at the tires...

 

[Mr. Breeze]

I did get an alignment, and to answer MrBoJangles I did use the shims that came with the kit. I've also got a fairly new air filter installed and cleaned the MAF sensor about a month ago. I was thinking of replacing spark plugs and coils next.

It's an '05 btw.

This is getting frustrating. I'm down to 12 mpg now. My 15,000 lb, V10 powered RV gets 10. Thanks everyone.

 

[4thNissan'05]

It's gotta be either spark or injection at this point, I would think.

 

[10935]

Down to about 12.2mpg. Does anyone have any ideas as to why I dropped so much so fast?

Mine has been that way since I lifted and installed heavy tires(almost 4 years now). Sorta just the way it is...

 

[Mr. Breeze]

Mine has been that way since I lifted and installed heavy tires(almost 4 years now). Sorta just the way it is...

Ugh... I haven't even changed tires. Yet.

 

[4thNissan'05]

THe only thing I haven't mentioned is the vacuum lines... but that's getting down to the nitty gritty of my knowledge. Best of luck! Keep in mind... I only get 13.4 MPG as it is.